protocol

`s3_protocol`

S3-compatible client facade predicates.

Availability:

logtalk_load(s3(loader))

Author: Paulo Moura
Version: 1:0:0
Date: 2026-07-13

Compilation flags:

static

Dependencies:

(none)

Remarks:

(none)

Inherited public predicates:

(none)

Public predicates 

`list_buckets/2`

Lists accessible buckets.

Compilation flags:

static

Template:

list_buckets(Buckets,Options)

Mode and number of proofs:

list_buckets(-compound,+list(compound)) - one_or_error

Exceptions:

Options is a variable:

instantiation_error

Options is neither a variable nor a list:

type_error(list,Options)

An element Option of the list Options is a variable:

instantiation_error

An element Option of the list Options is neither a variable nor a compound term:

type_error(compound,Option)

An element Option of the list Options is a compound term but not a valid option:

domain_error(option,Option)

Options contains an invalid S3 client option:

domain_error(s3_client_option,Option)

Credentials are missing or invalid:

domain_error(s3_credentials,missing)

The S3 service returned a non-success status or malformed XML body:

domain_error(s3_http_status,Status)

Remarks:

Option credentials/1: Required access credentials as credentials(access_key_id(AccessKeyId), secret_access_key(SecretAccessKey)).

Option session_token/1: Optional session token for temporary credentials.

Option region/1: AWS region to use when endpoint/1 is absent. Defaults to us-east-1.

Option endpoint/1: Optional custom S3-compatible endpoint URL.

Option addressing_style/1: Endpoint addressing style, either virtual_hosted or path. Defaults to virtual_hosted.

Option headers/1: Optional extra normalized HTTP request headers.

Option version/1: HTTP protocol version as http(Major, Minor). Defaults to http(1,1).

Option properties/1: Optional extra normalized HTTP request properties.

Option connection_options/1: Optional transport-specific HTTP client options.

Option payload_hash_mode/1: Payload signing mode, either signed or unsigned. Defaults to signed.

Option request_time/1: Optional explicit local request time as date_time(Year, Month, Day, Hours, Minutes, Seconds).

Option utc_offset_seconds/1: UTC offset used to derive the signing time from the local clock. Defaults to 0.

Option amz_date/1: Optional explicit AWS SigV4 timestamp overriding any derived request time.

`head_bucket/3`

Returns response metadata for a bucket.

Compilation flags:

static

Template:

head_bucket(Bucket,Metadata,Options)

Mode and number of proofs:

head_bucket(+atom,-compound,+list(compound)) - one_or_error

Exceptions:

Bucket is a variable:

instantiation_error

Bucket is neither a variable nor an atom:

type_error(atom,Bucket)

Bucket is an atom but not a valid S3 bucket:

domain_error(s3_bucket,Bucket)

Options is a variable:

instantiation_error

Options is neither a variable nor a list:

type_error(list,Options)

An element Option of the list Options is a variable:

instantiation_error

An element Option of the list Options is neither a variable nor a compound term:

type_error(compound,Option)

An element Option of the list Options is a compound term but not a valid option:

domain_error(option,Option)

Options contains an invalid S3 client option:

domain_error(s3_client_option,Option)

The S3 service returned a non-success status:

domain_error(s3_http_status,Status)

Remarks:

Options: Supported options are the standard S3 request options: credentials(access_key_id(AccessKeyId), secret_access_key(SecretAccessKey)), optional session_token(Token), region(Region), optional custom endpoint(URL), addressing_style(virtual_hosted|path), optional headers(Headers), version(http(Major, Minor)), optional properties(Properties), optional connection_options(ConnectionOptions), payload_hash_mode(signed|unsigned), optional request_time(date_time(...)), utc_offset_seconds(OffsetSeconds), and optional explicit amz_date(AmzDate).

`list_objects_v2/4`

Lists bucket objects using the ListObjectsV2 API.

Compilation flags:

static

Template:

list_objects_v2(Bucket,Request,Listing,Options)

Mode and number of proofs:

list_objects_v2(+atom,+compound,-compound,+list(compound)) - one_or_error

Exceptions:

Bucket is a variable:

instantiation_error

Request is a variable:

instantiation_error

An element Option of the request option list is a variable:

instantiation_error

Bucket is neither a variable nor an atom:

type_error(atom,Bucket)

An element Option of the request option list is neither a variable nor a compound term:

type_error(compound,Option)

Bucket is an atom but not a valid S3 bucket:

domain_error(s3_bucket,Bucket)

Request is not a valid ListObjectsV2 request term or option list:

domain_error(s3_list_objects_request,Request)

An element Option of the request option list is a compound term but not a valid ListObjectsV2 request option:

domain_error(s3_list_objects_request_option,Option)

Options is a variable:

instantiation_error

Options is neither a variable nor a list:

type_error(list,Options)

An element Option of the list Options is a variable:

instantiation_error

An element Option of the list Options is neither a variable nor a compound term:

type_error(compound,Option)

An element Option of the list Options is a compound term but not a valid option:

domain_error(option,Option)

Options contains an invalid S3 client option:

domain_error(s3_client_option,Option)

The S3 service returned a non-success status or malformed XML body:

domain_error(s3_http_status,Status)

Remarks:

Options: Options accepts the standard S3 request options: credentials(access_key_id(AccessKeyId), secret_access_key(SecretAccessKey)), optional session_token(Token), region(Region), optional custom endpoint(URL), addressing_style(virtual_hosted|path), optional headers(Headers), version(http(Major, Minor)), optional properties(Properties), optional connection_options(ConnectionOptions), payload_hash_mode(signed|unsigned), optional request_time(date_time(...)), utc_offset_seconds(OffsetSeconds), and optional explicit amz_date(AmzDate). The Request argument carries the ListObjectsV2-specific request options.

`head_object/4`

Returns response metadata for an object.

Compilation flags:

static

Template:

head_object(Bucket,Key,Metadata,Options)

Mode and number of proofs:

head_object(+atom,+atom,-compound,+list(compound)) - one_or_error

Exceptions:

Bucket is a variable:

instantiation_error

Key is a variable:

instantiation_error

Bucket is neither a variable nor an atom:

type_error(atom,Bucket)

Key is neither a variable nor an atom:

type_error(atom,Key)

Bucket is an atom but not a valid S3 bucket:

domain_error(s3_bucket,Bucket)

Options is a variable:

instantiation_error

Options is neither a variable nor a list:

type_error(list,Options)

An element Option of the list Options is a variable:

instantiation_error

An element Option of the list Options is neither a variable nor a compound term:

type_error(compound,Option)

An element Option of the list Options is a compound term but not a valid option:

domain_error(option,Option)

Options contains an invalid S3 client option:

domain_error(s3_client_option,Option)

The S3 service returned a non-success status:

domain_error(s3_http_status,Status)

Remarks:

Options: Supported options are the standard S3 request options: credentials(access_key_id(AccessKeyId), secret_access_key(SecretAccessKey)), optional session_token(Token), region(Region), optional custom endpoint(URL), addressing_style(virtual_hosted|path), optional headers(Headers), version(http(Major, Minor)), optional properties(Properties), optional connection_options(ConnectionOptions), payload_hash_mode(signed|unsigned), optional request_time(date_time(...)), utc_offset_seconds(OffsetSeconds), and optional explicit amz_date(AmzDate).

`get_object/5`

Fetches an object into a local file path and returns its response metadata as a separate argument.

Compilation flags:

static

Template:

get_object(Bucket,Key,File,Properties,Options)

Mode and number of proofs:

get_object(+atom,+atom,+atom,-compound,+list(compound)) - one_or_error

Exceptions:

Bucket is a variable:

instantiation_error

Key is a variable:

instantiation_error

File is a variable:

instantiation_error

Bucket is neither a variable nor an atom:

type_error(atom,Bucket)

Key is neither a variable nor an atom:

type_error(atom,Key)

File is neither a variable nor an atom:

type_error(atom,File)

Bucket is an atom but not a valid S3 bucket:

domain_error(s3_bucket,Bucket)

File exists but is not a writable file:

domain_error(file([],[write]),File)

The directory Directory exists but is not writable:

domain_error(directory([write]),Directory)

The directory Directory does not exist:

existence_error(directory,Directory)

Options is a variable:

instantiation_error

Options is neither a variable nor a list:

type_error(list,Options)

An element Option of the list Options is a variable:

instantiation_error

An element Option of the list Options is neither a variable nor a compound term:

type_error(compound,Option)

An element Option of the list Options is a compound term but not a valid option:

domain_error(option,Option)

Options contains an invalid S3 client option:

domain_error(s3_client_option,Option)

The S3 service returned a non-success status:

domain_error(s3_http_status,Status)

Remarks:

Options: Supported options are: credentials(access_key_id(AccessKeyId), secret_access_key(SecretAccessKey)) for access credentials; session_token(Token) for temporary credentials; region(Region) for the AWS region, defaulting to us-east-1 when endpoint/1 is absent; endpoint(URL) for a custom S3-compatible endpoint; addressing_style(virtual_hosted|path) for endpoint addressing, defaulting to virtual_hosted; headers(Headers) for extra normalized request headers; version(http(Major, Minor)) for the HTTP protocol version, defaulting to http(1,1); properties(Properties) for extra normalized HTTP request properties; connection_options(ConnectionOptions) for transport-specific HTTP client options; payload_hash_mode(signed|unsigned) for payload signing, defaulting to signed; request_time(date_time(...)) for an explicit local request time; utc_offset_seconds(OffsetSeconds) for deriving UTC from the local clock, defaulting to 0; and amz_date(AmzDate) for an explicit AWS SigV4 timestamp overriding time derivation.

`put_object/6`

Uploads a local file path and returns the object ETag and response metadata as separate arguments.

Compilation flags:

static

Template:

put_object(Bucket,Key,File,ETag,Properties,Options)

Mode and number of proofs:

put_object(+atom,+atom,+atom,-atom,-compound,+list(compound)) - one_or_error

Exceptions:

Bucket is a variable:

instantiation_error

Key is a variable:

instantiation_error

File is a variable:

instantiation_error

Bucket is neither a variable nor an atom:

type_error(atom,Bucket)

Key is neither a variable nor an atom:

type_error(atom,Key)

File is neither a variable nor an atom:

type_error(atom,File)

Bucket is an atom but not a valid S3 bucket:

domain_error(s3_bucket,Bucket)

File exists but is not a readable file:

domain_error(file([],[read]),File)

The file File does not exist:

existence_error(file,File)

Options is a variable:

instantiation_error

Options is neither a variable nor a list:

type_error(list,Options)

An element Option of the list Options is a variable:

instantiation_error

An element Option of the list Options is neither a variable nor a compound term:

type_error(compound,Option)

An element Option of the list Options is a compound term but not a valid option:

domain_error(option,Option)

Options contains an invalid S3 client option:

domain_error(s3_client_option,Option)

The S3 service returned a non-success status:

domain_error(s3_http_status,Status)

Remarks:

Options: Supported options are the standard S3 request options: credentials(access_key_id(AccessKeyId), secret_access_key(SecretAccessKey)), optional session_token(Token), region(Region), optional custom endpoint(URL), addressing_style(virtual_hosted|path), optional headers(Headers), version(http(Major, Minor)), optional properties(Properties), optional connection_options(ConnectionOptions), payload_hash_mode(signed|unsigned), optional request_time(date_time(...)), utc_offset_seconds(OffsetSeconds), and optional explicit amz_date(AmzDate).

`delete_object/4`

Deletes an object, returning delete_result(Properties).

Compilation flags:

static

Template:

delete_object(Bucket,Key,Result,Options)

Mode and number of proofs:

delete_object(+atom,+atom,-compound,+list(compound)) - one_or_error

Exceptions:

Bucket is a variable:

instantiation_error

Key is a variable:

instantiation_error

Bucket is neither a variable nor an atom:

type_error(atom,Bucket)

Key is neither a variable nor an atom:

type_error(atom,Key)

Bucket is an atom but not a valid S3 bucket:

domain_error(s3_bucket,Bucket)

Options is a variable:

instantiation_error

Options is neither a variable nor a list:

type_error(list,Options)

An element Option of the list Options is a variable:

instantiation_error

An element Option of the list Options is neither a variable nor a compound term:

type_error(compound,Option)

An element Option of the list Options is a compound term but not a valid option:

domain_error(option,Option)

Options contains an invalid S3 client option:

domain_error(s3_client_option,Option)

The S3 service returned a non-success status:

domain_error(s3_http_status,Status)

Remarks:

Options: Supported options are the standard S3 request options: credentials(access_key_id(AccessKeyId), secret_access_key(SecretAccessKey)), optional session_token(Token), region(Region), optional custom endpoint(URL), addressing_style(virtual_hosted|path), optional headers(Headers), version(http(Major, Minor)), optional properties(Properties), optional connection_options(ConnectionOptions), payload_hash_mode(signed|unsigned), optional request_time(date_time(...)), utc_offset_seconds(OffsetSeconds), and optional explicit amz_date(AmzDate).

`copy_object/5`

Copies an object from a source bucket/key into the destination bucket/key, returning copy_result(ETag, Properties).

Compilation flags:

static

Template:

copy_object(Source,Bucket,Key,Result,Options)

Mode and number of proofs:

copy_object(+compound,+atom,+atom,-compound,+list(compound)) - one_or_error

Exceptions:

Source is a variable:

instantiation_error

Bucket is a variable:

instantiation_error

Key is a variable:

instantiation_error

The version identifier in Source is a variable:

instantiation_error

Source is neither a variable nor a compound term:

type_error(compound,Source)

Bucket is neither a variable nor an atom:

type_error(atom,Bucket)

Key is neither a variable nor an atom:

type_error(atom,Key)

The version identifier in Source is neither a variable nor an atom:

type_error(atom,VersionId)

Source is a compound term but not a valid copy source term:

domain_error(s3_copy_source,Source)

Bucket is an atom but not a valid S3 bucket:

domain_error(s3_bucket,Bucket)

The version identifier in Source is an atom but not a valid version identifier:

domain_error(s3_version_id,VersionId)

Options is a variable:

instantiation_error

Options is neither a variable nor a list:

type_error(list,Options)

An element Option of the list Options is a variable:

instantiation_error

An element Option of the list Options is neither a variable nor a compound term:

type_error(compound,Option)

An element Option of the list Options is a compound term but not a valid option:

domain_error(option,Option)

Options contains an invalid S3 client option:

domain_error(s3_client_option,Option)

The S3 service returned a non-success status or malformed XML body:

domain_error(s3_http_status,Status)

Remarks:

Options: Supported options are the standard S3 request options: credentials(access_key_id(AccessKeyId), secret_access_key(SecretAccessKey)), optional session_token(Token), region(Region), optional custom endpoint(URL), addressing_style(virtual_hosted|path), optional headers(Headers), version(http(Major, Minor)), optional properties(Properties), optional connection_options(ConnectionOptions), payload_hash_mode(signed|unsigned), optional request_time(date_time(...)), utc_offset_seconds(OffsetSeconds), and optional explicit amz_date(AmzDate).

`presigned_get_object/4`

Generates a presigned URL for downloading an object with an external HTTP client.

Compilation flags:

static

Template:

presigned_get_object(Bucket,Key,URL,Options)

Mode and number of proofs:

presigned_get_object(+atom,+atom,-atom,+list(compound)) - one_or_error

Exceptions:

Bucket is a variable:

instantiation_error

Key is a variable:

instantiation_error

Bucket is neither a variable nor an atom:

type_error(atom,Bucket)

Key is neither a variable nor an atom:

type_error(atom,Key)

Bucket is an atom but not a valid S3 bucket:

domain_error(s3_bucket,Bucket)

Options is a variable:

instantiation_error

Options is neither a variable nor a list:

type_error(list,Options)

An element Option of the list Options is a variable:

instantiation_error

An element Option of the list Options is neither a variable nor a compound term:

type_error(compound,Option)

An element Option of the list Options is a compound term but not a valid option:

domain_error(option,Option)

Options contains an invalid S3 client option:

domain_error(s3_client_option,Option)

Credentials are missing or invalid:

domain_error(s3_credentials,missing)

The expiration is invalid or outside the AWS SigV4 range:

domain_error(s3_presign_expires,Expires)

The payload hash is missing, invalid, or incompatible with unsigned mode:

domain_error(s3_presign_payload_hash,Hash)

Remarks:

Option credentials/1: Required access credentials as credentials(access_key_id(AccessKeyId), secret_access_key(SecretAccessKey)).

Option session_token/1: Optional session token for temporary credentials.

Option region/1: AWS region to use when endpoint/1 is absent. Defaults to us-east-1.

Option endpoint/1: Optional custom S3-compatible endpoint URL.

Option addressing_style/1: Endpoint addressing style, either virtual_hosted or path. Defaults to virtual_hosted.

Option headers/1: Optional extra normalized request headers. When present they are signed into the URL and must be reproduced by the eventual caller.

Option payload_hash_mode/1: Presigned URLs default to payload_hash_mode(unsigned). Use signed together with payload_hash/1 to sign a precomputed payload hash.

Option payload_hash/1: Precomputed hexadecimal SHA-256 payload hash required when payload_hash_mode(signed) is selected.

Option request_time/1: Optional explicit local request time as date_time(Year, Month, Day, Hours, Minutes, Seconds).

Option utc_offset_seconds/1: UTC offset used to derive the signing time from the local clock. Defaults to 0.

Option amz_date/1: Optional explicit AWS SigV4 timestamp overriding any derived request time.

Option expires/1: Presigned URL lifetime in seconds. Defaults to 900 and must not exceed 604800.

`presigned_put_object/4`

Generates a presigned URL for uploading an object with an external HTTP client.

Compilation flags:

static

Template:

presigned_put_object(Bucket,Key,URL,Options)

Mode and number of proofs:

presigned_put_object(+atom,+atom,-atom,+list(compound)) - one_or_error

Exceptions:

Bucket is a variable:

instantiation_error

Key is a variable:

instantiation_error

Bucket is neither a variable nor an atom:

type_error(atom,Bucket)

Key is neither a variable nor an atom:

type_error(atom,Key)

Bucket is an atom but not a valid S3 bucket:

domain_error(s3_bucket,Bucket)

Options is a variable:

instantiation_error

Options is neither a variable nor a list:

type_error(list,Options)

An element Option of the list Options is a variable:

instantiation_error

An element Option of the list Options is neither a variable nor a compound term:

type_error(compound,Option)

An element Option of the list Options is a compound term but not a valid option:

domain_error(option,Option)

Options contains an invalid S3 client option:

domain_error(s3_client_option,Option)

Credentials are missing or invalid:

domain_error(s3_credentials,missing)

The expiration is invalid or outside the AWS SigV4 range:

domain_error(s3_presign_expires,Expires)

The payload hash is missing, invalid, or incompatible with unsigned mode:

domain_error(s3_presign_payload_hash,Hash)

Remarks:

Option credentials/1: Required access credentials as credentials(access_key_id(AccessKeyId), secret_access_key(SecretAccessKey)).

Option session_token/1: Optional session token for temporary credentials.

Option region/1: AWS region to use when endpoint/1 is absent. Defaults to us-east-1.

Option endpoint/1: Optional custom S3-compatible endpoint URL.

Option addressing_style/1: Endpoint addressing style, either virtual_hosted or path. Defaults to virtual_hosted.

Option headers/1: Optional extra normalized request headers. When present they are signed into the URL and must be reproduced by the eventual caller.

Option payload_hash_mode/1: Presigned URLs default to payload_hash_mode(unsigned). Use signed together with payload_hash/1 to sign a precomputed payload hash.

Option payload_hash/1: Precomputed hexadecimal SHA-256 payload hash required when payload_hash_mode(signed) is selected.

Option request_time/1: Optional explicit local request time as date_time(Year, Month, Day, Hours, Minutes, Seconds).

Option utc_offset_seconds/1: UTC offset used to derive the signing time from the local clock. Defaults to 0.

Option amz_date/1: Optional explicit AWS SigV4 timestamp overriding any derived request time.

Option expires/1: Presigned URL lifetime in seconds. Defaults to 900 and must not exceed 604800.

`presigned_post_object/4`

Generates a presigned URL for a POST request to an object with an external HTTP client.

Compilation flags:

static

Template:

presigned_post_object(Bucket,Key,URL,Options)

Mode and number of proofs:

presigned_post_object(+atom,+atom,-atom,+list(compound)) - one_or_error

Exceptions:

Bucket is a variable:

instantiation_error

Key is a variable:

instantiation_error

Bucket is neither a variable nor an atom:

type_error(atom,Bucket)

Key is neither a variable nor an atom:

type_error(atom,Key)

Bucket is an atom but not a valid S3 bucket:

domain_error(s3_bucket,Bucket)

Options is a variable:

instantiation_error

Options is neither a variable nor a list:

type_error(list,Options)

An element Option of the list Options is a variable:

instantiation_error

An element Option of the list Options is neither a variable nor a compound term:

type_error(compound,Option)

An element Option of the list Options is a compound term but not a valid option:

domain_error(option,Option)

Options contains an invalid S3 client option:

domain_error(s3_client_option,Option)

Credentials are missing or invalid:

domain_error(s3_credentials,missing)

The expiration is invalid or outside the AWS SigV4 range:

domain_error(s3_presign_expires,Expires)

The payload hash is missing, invalid, or incompatible with unsigned mode:

domain_error(s3_presign_payload_hash,Hash)

Remarks:

Option credentials/1: Required access credentials as credentials(access_key_id(AccessKeyId), secret_access_key(SecretAccessKey)).

Option session_token/1: Optional session token for temporary credentials.

Option region/1: AWS region to use when endpoint/1 is absent. Defaults to us-east-1.

Option endpoint/1: Optional custom S3-compatible endpoint URL.

Option addressing_style/1: Endpoint addressing style, either virtual_hosted or path. Defaults to virtual_hosted.

Option headers/1: Optional extra normalized request headers. When present they are signed into the URL and must be reproduced by the eventual caller.

Option payload_hash_mode/1: Presigned URLs default to payload_hash_mode(unsigned). Use signed together with payload_hash/1 to sign a precomputed payload hash.

Option payload_hash/1: Precomputed hexadecimal SHA-256 payload hash required when payload_hash_mode(signed) is selected.

Option request_time/1: Optional explicit local request time as date_time(Year, Month, Day, Hours, Minutes, Seconds).

Option utc_offset_seconds/1: UTC offset used to derive the signing time from the local clock. Defaults to 0.

Option amz_date/1: Optional explicit AWS SigV4 timestamp overriding any derived request time.

Option expires/1: Presigned URL lifetime in seconds. Defaults to 900 and must not exceed 604800.

Protected predicates 

(none)

Private predicates 

(none)

Operators 

(none)

s3_protocol

`s3_protocol`